LONDON, UK: Global oil markets could face prolonged disruption as shipping bottlenecks, refinery outages and depleted inventories continue to strain supplies, with industry executives warning on that some effects of the Iran war could persist for years.

The U.S.-Israeli war on Iran, which began at the end of February, has effectively closed the Strait of Hormuz, choking exports through one of the world's most crucial shipping bottlenecks.

Attacks on oil and gas infrastructure have compounded the impact, hampering production and disrupting exports of crude oil and refined fuels.

"I think it is going to be bedlam for the bulk of the end of the year and maybe 2027," Petronas CEO Tengku Muhammad Taufik said.

Amin Nasser, chief executive of Saudi Aramco, the world's biggest oil company, told the Energy Intelligence Forum in London that replenishing global stockpiles drawn down as an emergency measure could take up to two years.

"Until Hormuz fully reopens and confidence returns, the crude reality is that pressure at both ends of the barrel will intensify. Even then, replenishing inventories while meeting demand could take up to two years," he said. " Both ends of the barrel" refers to unrefined crude and refined products, such as diesel and jet fuel.

Nasser said three billion barrels have been lost since the conflict began and one billion barrels have been withdrawn from global inventories.

Kuwait Petroleum Corporation CEO Shaikh Nawaf Al-Sabah said efforts were focused on moving more refined fuels to global markets and restoring Middle East refineries to full production. The Iran war has left the world with a shortfall of six million barrels per day of refined products.

"There is not enough refining capacity in the world to make up for shuttered capacity in the Middle East Gulf," Shaikh Nawaf said.

Kuwait's crude oil exports have remained at around 1 million bpd this year despite war-related disruptions, even as production has fallen from about 2.6 million bpd to two million bpd, Al-Sabah told the conference.

ConocoPhillips Executive Chair Ryan Lance said global oil demand may not recover from this year's decline until 2028 or 2029, although he expected it to grow after that.

Lance said the price floor for U.S. benchmark WTI crude would rise to around US$70 per barrel, with a mid-cycle price of $65 to $70 per barrel.

U.S. oil production could exceed 14 million to 14.5 million barrels per day if prices remain strong, he said, without specifying what he meant by strong prices.

Brent crude futures traded just above $100 per barrel on Monday, while WTI was close to $90 per barrel.